1. Field of the Invention
The invention in general relates to means for monitoring the position of the piston in a predetermined combustion cylinder of an Otto cycle engine and, more particularly, it relates to a rotor or trigger wheel arrangement cooperating with a hall generator useful for detecting the precise position of a piston and, hence, the rotational angle or position of a crank shaft in an internal combustion engine.
2. Description of the State of the Art
Hall generators have found wide application in modern Otto cycle engines for the generation of signals relating to a predetermined position, for instance dead center, of the piston within a cylinder. The signals may be utilized for the control of ignition timing.
The signals may be generated by a trigger wheel provided in the distributor of an engine. Gaps or indentations may be provided in the wheel which may be monitored by a Hall element. Other signal generating markings, such as photocells, reed relays, magnets and the like, may, of course, also be used.
While such trigger elements are generally capable of detecting the position, such as dead center, of a piston within a combustion cylinder, they cannot generate selective cylinder signals i.e. signals representative of a predetermined cylinder. In order to generate such signals it would be necessary to feed to an associated logic control some kind of a signal representative of the initiation of the 720.degree. operational cycle of a four-cycle engine.